Abstract: SA-PO0851
Integrating Vascular Injury into Risk Prediction: Renal Thrombotic Microangiopathy in Lupus Nephritis Outcomes
Session Information
- Glomerular Diseases: Management, Evolving Strategies, and Practice-Changing Advances
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Thawornkaew, Supawas, Chulalongkorn University Faculty of Medicine, Bangkok, Thailand
- Kanjanabuch, Talerngsak, Chulalongkorn University Faculty of Medicine, Bangkok, Thailand
Background
Renal thrombotic microangiopathy (TMA) is an underrecognized vascular lesion in lupus nephritis (LN), and its independent prognostic value remains uncertain.
Methods
We studied 452 patients with biopsy-proven LN at King Chulalongkorn Memorial Hospital from 2012-2024; 64 (14.2%) had renal TMA on index biopsy. Kidney failure was the primary outcome. Cox regression was the primary analysis, with Fine-Gray competing-risk, composite-outcome, and multiple-imputation analyses used for confirmation. A biopsy-based TMA-Chronicity Kidney Failure (TCKF) score was internally validated by 500 bootstrap replications.
Results
Compared with non-TMA LN, TMA was associated with higher systolic blood pressure, edema, activity/chronicity indices, impaired kidney function, cytopenia, lower C3, and more antiphospholipid antibody positivity. Kidney failure occurred in 50.9% with TMA versus 9.8% without TMA (P<0.001); mortality was higher (12.5% vs 2.8%; P<0.001). Renal TMA independently predicted kidney failure (adjusted HR, 2.45; 95% CI, 1.39–4.32; P=0.002). Adding TMA improved model fit (likelihood ratio P=0.012) and discrimination (Harrell’s C=0.86; optimism-corrected C=0.85). The TCKF score stratified 5-year kidney failure incidence into low, intermediate, and high risk: 4%, 35%, and 72% (Gray’s P<0.001).
Conclusion
Renal TMA defines a high-risk vascular phenotype in LN and independently predicts kidney failure and mortality. The TCKF score enables bedside risk stratification and may guide therapy.
Acknowledgment
The authors gratefully acknowledge all patients whose clinical data contributed to this study, enabling advancement in the understanding of renal thrombotic microangiopathy in lupus nephritis. We acknowledge the physicians, nurses, and staff of the Division of Nephrology, Faculty of Medicine, Chulalongkorn University, and King Chulalongkorn Memorial Hospital, as well as the pathology team, for their dedication to patient care and their essential role in data collection and biopsy evaluation.
Kidney failure by renal TMA status in lupus nephritis.
Cumulative incidence of kidney failure by TCKF risk group.